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International Cooperative Programme on Assessment and Monitoring of the Effects of Air Pollution on Rivers and Lakes

Chair: Ms. Heleen de Wit
Head of Programme Centre:  Ms. Kari Austnes

Acidification of freshwater systems provided some of the earliest evidence of the damage caused by sulphur emissions. The sensitivity of these systems suggested that they were ideal for studying the effects of and response to changes in atmospheric pollution. 

To assess, on a regional basis, the degree and geographical extent of the impact of atmospheric pollution, in particular acidification, on surface waters, the International Cooperative Programme on Assessment and Monitoring of the Effects of Air Pollution on Rivers and Lakes (ICP Waters) was established in 1985.    

ICP Waters collects and assesses lake and stream monitoring data from an extensive network of monitoring sites. The monitoring includes both chemistry and biology. All major chemical constituents are included in the analytical programme. Biological data is derived from monitoring of fish populations, invertebrates and algae which show different tolerance to water chemistry conditions, among others. Data on changes in these populations can thus be important indicators of water quality. Chemical and biological data are used to assess temporal trends and spatial patterns, as well as evaluations of dose/response relationships. Assessing the impact of confounding factors such as climate change and land use change is becoming increasingly important.

Quality control is an important part of the programme. Annual laboratory intercalibration exercises were established in 1987, involving, about 35 laboratories in around 20 countries each year for chemical parameters. There is also intercalibration for invertebrate taxonomic identification. Database checks ensure the quality of the data which are being collected and used. Maintaining and updating a manual of recommended methods promotes harmonisation of methods. 

The Programme is planned and coordinated by a Task Force under the leadership of Norway, through the Norwegian Institute for Water Research (NIVA). Task Force meetings are held annually. Chemical and site data from about 550 catchments in around 20 countries in Europe and North America are available in the database of the Programme Centre at NIVA. A sub-centre of ICP Waters with special responsibility for biological data and intercalibration is located at NORCE Norwegian Research Centre.

The revised mandate for ICP Waters can be found in EB decision 2019/15.

Further information including publications is available from the Programme Centre.

Reports of ICP Waters